Phantomexposure Sprite Spores is a free multi-chip synthesizer that gathers four families of vintage sound chips into one instrument, then adds tools the original hardware never had. Each chip, the AY/YM, the Commodore SID, and two Yamaha FM chips, opens as its own editable mini-synth, and a fictional Ghost ASIC engine handles unstable, evolving texture. You can blend any of them into a single playable patch.
Around the engines sit a drawable wavetable, a chord system, three polymetric sequencer lanes, the Sprout musical randomizer, and a bank of effects modeled on decaying video memory: bitplanes, nibble swaps and register interference used as an instrument. Reactive CRT displays and a live register-bus monitor make it part synth, part visualizer.
It is free, or pay what you want, as a Windows and macOS VST3, which makes it an easy addition next to other no-cost tools like Surge XT and Vital, and a companion to the same developer's Interphase Cartograph. For the full guide, see the Sprite Spores overview.